<?php
/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org> //
// available at http://getid3.sourceforge.net //
// or http://www.getid3.org //
/////////////////////////////////////////////////////////////////
// See readme.txt for more details //
/////////////////////////////////////////////////////////////////
// //
// module.audio.au.php //
// module for analyzing AU files //
// dependencies: NONE //
// ///
/////////////////////////////////////////////////////////////////
class getid3_au extends getid3_handler
{
function Analyze() {
$info = &$this->getid3->info;
fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);
$AUheader = fread($this->getid3->fp, 8);
$magic = '.snd';
if (substr($AUheader, 0, 4) != $magic) {
$info['error'][] = 'Expecting "'.getid3_lib::PrintHexBytes($magic).'" (".snd") at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes(substr($AUheader, 0, 4)).'"';
return false;
}
// shortcut
$info['au'] = array();
$thisfile_au = &$info['au'];
$info['fileformat'] = 'au';
$info['audio']['dataformat'] = 'au';
$info['audio']['bitrate_mode'] = 'cbr';
$thisfile_au['encoding'] = 'ISO-8859-1';
$thisfile_au['header_length'] = getid3_lib::BigEndian2Int(substr($AUheader, 4, 4));
$AUheader .= fread($this->getid3->fp, $thisfile_au['header_length'] - 8);
$info['avdataoffset'] += $thisfile_au['header_length'];
$thisfile_au['data_size'] = getid3_lib::BigEndian2Int(substr($AUheader, 8, 4));
$thisfile_au['data_format_id'] = getid3_lib::BigEndian2Int(substr($AUheader, 12, 4));
$thisfile_au['sample_rate'] = getid3_lib::BigEndian2Int(substr($AUheader, 16, 4));
$thisfile_au['channels'] = getid3_lib::BigEndian2Int(substr($AUheader, 20, 4));
$thisfile_au['comments']['comment'][] = trim(substr($AUheader, 24));
$thisfile_au['data_format'] = $this->AUdataFormatNameLookup($thisfile_au['data_format_id']);
$thisfile_au['used_bits_per_sample'] = $this->AUdataFormatUsedBitsPerSampleLookup($thisfile_au['data_format_id']);
if ($thisfile_au['bits_per_sample'] = $this->AUdataFormatBitsPerSampleLookup($thisfile_au['data_format_id'])) {
$info['audio']['bits_per_sample'] = $thisfile_au['bits_per_sample'];
} else {
unset($thisfile_au['bits_per_sample']);
}
$info['audio']['sample_rate'] = $thisfile_au['sample_rate'];
$info['audio']['channels'] = $thisfile_au['channels'];
if (($info['avdataoffset'] + $thisfile_au['data_size']) > $info['avdataend']) {
$info['warning'][] = 'Possible truncated file - expecting "'.$thisfile_au['data_size'].'" bytes of audio data, only found '.($info['avdataend'] - $info['avdataoffset']).' bytes"';
}
$info['playtime_seconds'] = $thisfile_au['data_size'] / ($thisfile_au['sample_rate'] * $thisfile_au['channels'] * ($thisfile_au['used_bits_per_sample'] / 8));
$info['audio']['bitrate'] = ($thisfile_au['data_size'] * 8) / $info['playtime_seconds'];
return true;
}
function AUdataFormatNameLookup($id) {
static $AUdataFormatNameLookup = array(
0 => 'unspecified format',
1 => '8-bit mu-law',
2 => '8-bit linear',
3 => '16-bit linear',
4 => '24-bit linear',
5 => '32-bit linear',
6 => 'floating-point',
7 => 'double-precision float',
8 => 'fragmented sampled data',
9 => 'SUN_FORMAT_NESTED',
10 => 'DSP program',
11 => '8-bit fixed-point',
12 => '16-bit fixed-point',
13 => '24-bit fixed-point',
14 => '32-bit fixed-point',
16 => 'non-audio display data',
17 => 'SND_FORMAT_MULAW_SQUELCH',
18 => '16-bit linear with emphasis',
19 => '16-bit linear with compression',
20 => '16-bit linear with emphasis + compression',
21 => 'Music Kit DSP commands',
22 => 'SND_FORMAT_DSP_COMMANDS_SAMPLES',
23 => 'CCITT g.721 4-bit ADPCM',
24 => 'CCITT g.722 ADPCM',
25 => 'CCITT g.723 3-bit ADPCM',
26 => 'CCITT g.723 5-bit ADPCM',
27 => 'A-Law 8-bit'
);
return (isset($AUdataFormatNameLookup[$id]) ? $AUdataFormatNameLookup[$id] : false);
}
function AUdataFormatBitsPerSampleLookup($id) {
static $AUdataFormatBitsPerSampleLookup = array(
1 => 8,
2 => 8,
3 => 16,
4 => 24,
5 => 32,
6 => 32,
7 => 64,
11 => 8,
12 => 16,
13 => 24,
14 => 32,
18 => 16,
19 => 16,
20 => 16,
23 => 16,
25 => 16,
26 => 16,
27 => 8
);
return (isset($AUdataFormatBitsPerSampleLookup[$id]) ? $AUdataFormatBitsPerSampleLookup[$id] : false);
}
function AUdataFormatUsedBitsPerSampleLookup($id) {
static $AUdataFormatUsedBitsPerSampleLookup = array(
1 => 8,
2 => 8,
3 => 16,
4 => 24,
5 => 32,
6 => 32,
7 => 64,
11 => 8,
12 => 16,
13 => 24,
14 => 32,
18 => 16,
19 => 16,
20 => 16,
23 => 4,
25 => 3,
26 => 5,
27 => 8,
);
return (isset($AUdataFormatUsedBitsPerSampleLookup[$id]) ? $AUdataFormatUsedBitsPerSampleLookup[$id] : false);
}
}
?>
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